JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 926 · 40 questions

Code tip (Line by line): let x = 5; makes a variable x holding 5; x = x + 2; changes it to 7. console.log(…) writes in the console; alert(…) shows a pop-up box. Text in quotes + anything = joined text: "5" + 3 → "53".

1. 1.⚡ What number does this code print?
   let a = 47;
   let b = 22;
   console.log(a - b);
2. 2.⚡ What does this code print? (Look at the quotes!)
   let x = "4";
   let y = 1;
   console.log(x + y); (a) Error (b) 41 (c) 5
3. 3.⚡ What does this code print? (Look at the quotes!)
   let x = "4";
   let y = 3;
   console.log(x + y); (a) 43 (b) 7 (c) Error
4. 4.⚡ What number does this code print?
   let a = 38;
   let b = 34;
   console.log(a - b);
5. 5.⚡ What does JavaScript add to a web page? (a) the page title (b) actions and changes (c) only colours (d) the domain name
6. 6.⚡ What number does this code print?
   let coins = 12;
   coins = coins + 17;
   coins = coins - 1;
   console.log(coins);
7. 7.⚡ What does this code print? (Look at the quotes!)
   let x = "6";
   let y = 2;
   console.log(x + y); (a) 62 (b) 8 (c) Error
8. 8.⚡ Which tag holds JavaScript in a page? (a) <js> (b) <code> (c) <script> (d) <style>
9. 9.⚡ What does this code print? (Look at the quotes!)
   let x = "6";
   let y = 5;
   console.log(x + y); (a) Error (b) 65 (c) 11
10. 10.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .js (c) .html (d) .jpg
11. 11.⚡ Which JavaScript word makes a new variable? (a) console.log() (b) for (c) alert() (d) let
12. 12.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 4;
    console.log(x + y); (a) 24 (b) Error (c) 6
13. 13.⚡ What does this code show?
    let name = "Zoya";
    alert("Hi, " + name + "!"); (a) name (b) Hi, Zoya! (c) Hi, name! (d) Zoya
14. 14.⚡ What number does this code print?
    let runs = 9;
    runs = runs + 16;
    runs = runs - 4;
    console.log(runs);
15. 15.⚡ Which JavaScript word runs code when true? (a) alert() (b) for (c) if (d) let
16. 16.⚡ What number does this code print?
    let a = 13;
    let b = 5;
    console.log(a + b);
17. 17.⚡ Which JavaScript word writes in the console? (a) if (b) console.log() (c) alert() (d) for
18. 18.⚡ What does this code show?
    let name = "Riya";
    console.log("Hi, " + name + "!"); (a) Hi, Riya! (b) name (c) Riya (d) Hi, name!
19. 19.⚡ What number does this code print?
    let a = 3;
    let b = 10;
    console.log(a * b);
20. 20.⚡ What number does this code print?
    let marks = 29;
    marks = marks + 14;
    marks = marks - 25;
    console.log(marks);
21. 21.⚡ Which word makes a new variable? (a) let (b) put (c) give (d) make
22. 22.⚡ What number does this code print?
    let a = 5;
    let b = 4;
    console.log(a * b);
23. 23.⚡ Which JavaScript word repeats code? (a) let (b) for (c) console.log() (d) if
24. 24.⚡ What number does this code print?
    let a = 8;
    let b = 8;
    console.log(a * b);
25. 25.⚡ What number does this code print?
    let apples = 30;
    apples = apples + 2;
    apples = apples - 10;
    console.log(apples);
26. 26.⚡ What number does this code print?
    let score = 28;
    score = score + 3;
    score = score - 1;
    console.log(score);
27. 27.⚡ What number does this code print?
    let a = 18;
    let b = 5;
    console.log(a - b);
28. 28.⚡ What number does this code print?
    let runs = 28;
    runs = runs + 12;
    runs = runs - 23;
    console.log(runs);
29. 29.⚡ What does this code show?
    let name = "Arjun";
    alert("Hello, " + name + "!"); (a) name (b) Hello, name! (c) Arjun (d) Hello, Arjun!
30. 30.⚡ What does this code show?
    let name = "Kabir";
    alert("Well done, " + name + "!"); (a) Well done, name! (b) name (c) Well done, Kabir! (d) Kabir
31. 31.⚡ What does this code show?
    let name = "Meera";
    console.log("Hello, " + name + "!"); (a) Hello, name! (b) name (c) Meera (d) Hello, Meera!
32. 32.⚡ What number does this code print?
    let apples = 14;
    apples = apples + 17;
    apples = apples - 9;
    console.log(apples);
33. 33.⚡ What number does this code print?
    let a = 23;
    let b = 10;
    console.log(a - b);
34. 34.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hello, " + name + "!"); (a) Kabir (b) Hello, name! (c) name (d) Hello, Kabir!
35. 35.⚡ What does alert() show? (a) a new tab (b) a table (c) a picture (d) a pop-up box
36. 36.⚡ What number does this code print?
    let a = 7;
    let b = 12;
    console.log(a * b);
37. 37.⚡ Which JavaScript word shows a pop-up box? (a) alert() (b) for (c) let (d) if
38. 38.⚡ What does this code show?
    let name = "Aman";
    alert("Hi, " + name + "!"); (a) Hi, name! (b) name (c) Aman (d) Hi, Aman!
39. 39.⚡ What number does this code print?
    let a = 57;
    let b = 11;
    console.log(a + b);
40. 40.⚡ What does this code show?
    let name = "Riya";
    alert("Hi, " + name + "!"); (a) Hi, name! (b) Riya (c) name (d) Hi, Riya!

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